1. Technical Field
The present invention concerns a turbine for a hydroelectric power station for generating electrical energy as well as a hydroelectric power station having a corresponding turbine.
2. Description of the Related Art
Hydroelectric power stations or hydroelectric power installations with turbines are known, which are divided substantially into three levels. The first level generally represents a support apparatus with which the turbine is held in its position in a passage. There is further provided a guide apparatus which is usually arranged in front of the rotor. Finally the rotor itself is arranged with the blades therebehind. That means that a flow in respect of a turbine of that kind is influenced at those three levels or locations.
‘Wasserkraftanlagen’ [‘Hydroelectric power installations’], 3rd edition, Springer Verlag 2003 by Jürgen Giesecke and Emil Mosonyi shows a number of hydroelectric power installations. Shown here for example is a Kaplan tube turbine. That turbine has an inlet shaft, the turbine and a suction hose, which are disposed very substantially in a line and are horizontal or slightly inclined relative to the horizontal. That has the advantage of avoiding a plurality of changes in the direction of flow, to the favor of a higher energy output. The turbine has support blades, guide blades and a rotor arranged therebehind, with corresponding blades.
Straight-flow turbine units are also known, wherein a generator is arranged concentrically outside the flow tube so that the generator is not disposed in the interior of the housing vessel. The rotor comprises a hub, rotor blades and a rotor ring, these being typically produced in the form of a welded structure to form a unit. A support cross arrangement is arranged in the flow direction upstream of the guide blades and the rotor with the rotor blades.
The guide apparatus arranged in front of the rotor is used by rotation of the guide blades or support blades to shut down the turbine by the blades being so set that they bear against each other and thus close the passage.
At this juncture attention is directed generally as state of the art to the following publications: DE 34 29 288 A1, DE 884 930 C, EP 0 622 543 A1, CH 332 959 and US No. 2005/0001432 A1.